Hand grenade



E. D. HIBBS HAND GRENADE Sept. 28, 1943.

2 Sheets-Sheet 1 [arid/[1M5 Filed March 22. 1941 Y 'ihl'ouwu Sept. 28, 1943. 1 mass 2,330,499

HAND GRENADE Filed March 22, 1941 2 Sheets-Sheet 2 3 [aria/712i:

Patented Sept. 28, 1943 'assogeo' HAND: GRENABE' 3, Earl.,D0ug lass,:Hibbs, lhiladelphia Pan" Application March 22, 194i; Serial- Noi 384,735:

2..o1aims.. (01. 102 -64) 'I his invention" relates to improvements in hand grenadesand more-particularlyf t'o-liand grenades which are adapted' to-be'released fordischarge by the-action of centrifugal force imparted to the g-renaadewhen-thrown.

" The use of explosive hand grenades is, of

course,- very oldl In the conventional hand grenade} ignition or detonation-is usually accomplished by a percussioncap or primer. Alocking pin or the likeis usually employedwhich, when withdrawn; sets the grenade for ignition of a Primer;

Agocd manydifficulties have existed'in connection with hand grenades' of the-prior-art. Due to the inherent danger of the hand grenade once it is releasedior firing; the thrower promptly-throws the hand grenade into" the region' of the enemy. However, many instances have been recorded Where, after removing the safety pinand before throwing the grenade, the; thrower has been wounded or killed and the live grenade has discharged in the'mid'st' of the throwers own com rades; Additionally, the handling in'transportation' of hand" grenades has been" highly precarious and"dangerous.

It'isan object of the present'inventmmnrst, to devisea hand grenade whichwill be so proportioned' and vformed -as to' meetthenatura'l' aptitude of the average soldier. In this connection,v the hand grenadeoflthe presentiinvention is madein precisely theishape and size of a standard'baseball; in the throwing of vwhich practically every soldier isproficient; v 7

Second, it is an object-of the present invention tonprovide a hand grenade in. such .formthat the firing. mechanism1.may be transported separately from the casingand' main explosive charge and neerlonly be assembled: in the fieldadjacent the point of use. In thisway the hazards. incident to transportation are practically completely clin inated;

.Third,,it is arrobjectlof the invention to provide ahan'd grenade whichimay be cheaply produced largely fromdiecastings andlpressings which can be, manufactured, and assembled, without expen: sive. machining operations. Further, and more detailed. objecta purposes, and advantages. of, the invention will become apparent as the description thereof proceeds.

Referring to the. drawings:

Figure. 11 is. as side elevation of a.. completely assembled hand grenadeviewedl from the side through. vwhich. theifiring, mechanismis mounted; Eigurez is. a=cross-sectiona1, view in the directionot'thearrows alcng line Z! of, Figurev 1';

- ;Figure S i'sa 'detaiIed' perspective-view or; m

sealingplug for the=firing-mechanism;

' Figure 4' is-* a' detailed perspective View of one form oflocking'pin bearingplate employed in the firing mechanism; 7

Figure 5 is'a detailed" perspective view of the fuse carrying casting suitably employed in; the

firingmechanism;

4 Figure 6is-a furtherdetailed view of a spacin ring employe'dint'he'firing mechanism; V Figure 7"is a-detailed'view ofthe'safety pin;

Figure" 8 is an exploded view' showing the mannerof assemblingjthe firing mechanism in the prechjarged grenade casing; j Figure 9 is a cross-sectional "vie w similar-to Figure 2 'but showing a" modified form of firing mechanism;

Figure I0'- aperspective View of the sealing plug, employed inv the 1 modification of V Figure" 9'; and y v i Figure: 1-1 isfadetailedperspective. view of 'the modified; form of" locking pin bearing plate employed in the structure offFi'gureii. I

7 Reierring' "to l Figure" 1, .the cast iron' casinggpf the hand g renade is" indicated generally j by the reference character l and is preferably, although notne'cessarilmgroovedlasindicated atZtQ insure that it will break up into small fragments when exploded: H Thegcasing l is provided'with' a comparatively small screwrthreaded. opening 3 gig i signedto receive thecclosing plug d, Thepurpose of the opening 3 is to pern'iit introduction of a molten explosive which is. cast about a. core on" the casing. I asindicated generally h in id @1 5: c I a The firingmechanism is indicated generally the reference character t",.and;its1relationship to the casing; hand" cast explosive 5'is 'particularly welljsho wn inliligure 8.. The casing [has a CQmrj paratively large screw-threaded opening:

' through which the entire firing mecham'sm an adapted. to be passed,. and, a" sealing plug. 8

screwed'into the casing through the. means of asuitable-wrench.fitting in the recesses 9 to bring.

the firing mechanism I 6" into fully assembled po-j I sition. 5 I i Referring to.Fi'gure 8,1 the core which is used in casting the explosive 5" in the casing Isuitj- 'ably takes, a form, precisely corresponding to the form o'fthe casing enclosingjthe, firing mecha nism 6; After'theexplosivejdis cast in the:cas.-

- ing [about the core; the coremay be'removed and the casing containing the, cast" explosive is then ready to be transported to the scene of ac; tion. Its will be observed that the interior wa'll intov the transverse bore 4|,

of the casing opposite the opening I is slightly recessed, as indicated at ID, to receive and seat the end of the detonator Coming to a description of the firing mechanism, it will be observed that the outer casing |2 thereof has its larger end fitted over the inner end of the sealing plug 8 with a rolled joint as indicated at 3. The smaller end of the casing |2 has an opening |4 through which the detonator extends. The open end of the explosion cap is flanged, as indicated at l5, and seats against the inner wall of the smaller end of the casing l2. The detonator contains a detonating charge of quick burning powder or other suitable 'primer which upon ignition ruptures the detonator thus setting ofi the main explosive grenade, when the casing I with its cast charge 5 and the firing mechanism 6, as shown in Figure 8, are separately received in the field, they are suitably assembled by inserting the firing mechanism through the opening I in the casing and screwing the plug 8 home which brings the end of the detonator into the recess Ill.

The thrower of the grenade then takes the hand grenade in his normal throwing hand, with the sealing plug 8 containing thesafety pin 44 positioned within the circle formed by the thumb and index finger, and then grasps the ring 45 of the safety pin 44 with his other hand and withexplosive.

Fitted into the casing l2 next to the open end of the detonator l is the'fuse and percussion cap carrying casting |6,.shown in detail in Figure 5. This casting is provided with a fuse carrying channel H which extends outwardly from a rupturable percussion cap l8 and communicates through an opening IS with a similar fuse channel which leads directly to the explosive charge in the detonator A centrally apertured disk 2| is seated immediately in advance of the fuse carrying casting I6. A spacing sleeve 22 abuts the disk 2|. A second substantially larger centrally apertured disk 23 is mounted immediately in advance of the spacing sleeve 22 with the central aperture 24 thereof ,afiording a bearing for the inner end of the firing pin 25. Immediately in front of the disk 23 is positioned a second spacing ring 26, shown in detail in Figure 6, which is provided at one side with a locking pin receiving opening 21 and at its opposite side with a keyway 28. The locking pin bearing disk 29 is press-fitted intothe' sleeve 26 with one arm 30 thereof in alignment with the opening 21 in the sleeve 26 and another arm 3| thereof. in align ment with the keyway 28 in the sleeve 26.

Struck out from the disk 29 are two inner hearing arms 32 and 33. The arms 3| and 32 are suitably apertured to receive the locking pin 34 while the arms 30 and 33 are apertured to receive the locking pin 35, The disk 29 also'has a central aperture 36 through which the firing pin extends. The locking pin 34 has rigidly connected therewith a weight 31, and locking pin 35 carries a corresponding weight 38 .v These weights 3|.and 38 are normally urged inwardly by the action of springs 39 and 40 seated, respectively, between the weight31 and arm 3| and the weight 38 and arm 30, theaction being such that the inner ends of the locking pins 34 and 35 extend which extends through the firing pin 25, and hold the same against any inward movement induced by the action of the spring 42.

The sealing plug 8 is fitted into the other end of. the casing l2 and, abuts the spacing ring 26. It completely seals the firing unit 6 of the grenade and has an opening therethrough, indicated at 43, to receive the partially split frictionally held safety pin 44 carrying the ring 45. The opening 43 in the sealing plug 8 is adapted to bepositioned in direct alignment with the keyway 28 in the sleeve 26 whereby the safety pin 44, ,when it is in the position shown in Figure 2, effectively locks thelocking pin 34 against outward movement and prevents unintentional release of the firing pin 25.

Now describing the operation of the hand draws the same. The hand grenade is then thrown in precisely the manner that a baseball is thrown. The'resulting centrifugal force causes the weights 3! and 38 to move radially outwardly, carrying with them the locking pins 34 and 35. The outer end of the locking pin 35 passes into the opening 21 in the sleeve 26, and the outer end of the locking pin 34 passes into the keyway 28 of the same sleeve. This results in a release of the firing pin 25, which, under the actionof the compression spring 42, is forcedthrough the central aperture of the disk 2| into the rupturable percussion cap l8, setting it off and igniting the fuse disposed in the communicating channel l1, l9, and 20. This channel is'of such length and proportions ,as to give a predetermined short time interval between the, time of release of the firing pin 25 and the explosion of the detonator H to thereby permit the hand grenade to arrive at its contemplated destination, at which point the rupture of the detonator sets off the main explosive charge, resulting in the disintegration of the casing with explosive effect. a

Referring to the modification shown in Figures 9 to 11, it will be observed that in this construction the disk 46 carrying the locking pin bearings is made to serve the purpose of the disk 23, sleeve 26, and plate 29 of the embodiment disclosed in Figures 1 to 8. This is achieved by forming the disk 45 with a diameter equal to the internal diameter of the larger portion of the casing l2, so that the disk46 may seat directly against the spacing ring'22, and by otherwise specially constructing the disk 46 as hereinafter explained. i

It will be observed that, in addition to, carrying locking pin bearing arms 30, 3|, 32, and 33, the disk 46 is provided with somewhat longer diametrically opposed legs 41' and 48. Thefree ends of these legs are designed to be received in and held by the notches 49 and 50 ofthe modi field sealing plug 5| shown in Figure 10. It will be noted that the notches 49 and 5B are each ninety degrees removed from the keyway 52 in the plug 5|. Thus, when the legs 41 and 48 of disk 46 are assembled with their free ends in notches 49 and 50 of sealing plug 5|, the keyway 52 will register with the outer surface of one of the bearing arms 30 or 3| in such manner that when the safety pin 44 is pressed into position, its free end will lie between one of thebearing arms 30 and 3| and the inner wall of the casing 2 to thereby effectively lock either the locking pin 34 or the locking pin 35 against radial movement, thus precluding unintentional release of the firing pin 25. In all other respects the modification of Figures 9 to 11 compares with the embodiment of Figures 1 to 8.

The modification of Figures 9 to 11 has certain advantages byway of simplication of construction and reduction in cost of manufacture and assembly. It will be observed that all of the elements entering into the hand grenade may be easily manufactured by well-known methods. The outer casing I is of cast metal. The only machining operations necessary comprise the threading of the openings 3 and 1. The plug 4 may be a die-cast suitably-threaded plug. The

sealing plug 8 and the fuse carrying casting 16 may likewise be produced by merely conventional die-casting methods. The casing I2, various disks, spacing rings, and bearing plates of the firing mechanism 6 are readily producible by diepressing and forming and may be easily assembled by relatively unskilled persons.

From the foregoing, it will be observed that the hand grenade of the present invention is highly effective, safe, extremely economical to produce, and especially advantageous from the standpoint of assembly and ability to separately transport the firing mechanism and the main explosive charge.

Having thus described my invention, I claim:

1. A hand grenade comprising, in combination, a precharged casing containing explosive molded to receive a firing mechanism and a separable firing assembly adapted to be inserted through an opening in a wall of said casing and to fit into the molded explosive therein, said firing mechanism embracing a metal casing carrying a precharged detonator at one end thereof, a preformed time fuse carrying member in juxtaposition to the charge of said detonator, a percussion cap associated with said member, a firing pin operable to strike said percussion cap to ignite said fuse, a centrally apertured disk surrounding said firing pin, diametrically opposed bearing arms on said disk,- radially disposed lockingpins carried by saidbearing arms, spring means urging said locking pins into contact with c said casing, said firing assembly comprising a,

detonator at the inner end of said recess, a time fuse and a percussion 'cap associated with said,

detonator, a spring actuated firing pin operable to strike said percussion cap, a centrally apertured disk surrounding said firing pin and overlying said. percussion cap,,a pair of radially spaced bearing arms extending upwardly from said disk, a locking pin carried by said bearing arms, resilient means urging said locking pin into contact with said firing'pin to maintain said firing pin spaced from said percussion'cap, a

weight carried by said locking pin responsive to centrifugal force to move said locking pinradial- Q 1y outward inopposition to Said resilient means to release, said firing pin, and a removable safety pin in contact with the outer end of said lock- "ing pin to positively prevent outward movement EARL DOUGLASS HIBBSQI 

